Study of Nimotuzumab and Irinotecan in Metastatic Colorectal Cancer

This study will determine if nimotuzumab provides a benefit in this type of cancer when given in combination with irinotecan.
The study will test:
* How long any good effects last.
* How bad any side effects are.
Objectives:
Primary:
The primary goal is to assess the Objective Response Rate (ORR) that the combination of irinotecan and nimotuzumab will produce in patients with irinotecan-refractory metastatic colorectal cancer
Secondary:
* To assess the incidence of Grade 2 or greater acneiform rash or infusion reaction, allergic reaction or anaphylactoid reaction AEs in patients with irinotecan-refractory metastatic colorectal cancer following weekly or 2-weekly nimotuzumab schedules;
* To assess Progression-Free Survival (PFS), defined as time from date of randomization until date of disease progression (clinical or radiological) or death due to any cause, for the two nimotuzumab schedules;
* To assess the rates and durations of Stable Disease (SD) following weekly or 2-weekly nimotuzumab schedules;
* To assess the Time to Disease Progression (TTP) following weekly or 2-weekly nimotuzumab schedules;
* To evaluate ORR in patients who are identified as having "primary" irinotecan resistance following weekly or 2-weekly nimotuzumab schedules;
* To evaluate Overall Survival (OS) following weekly or 2-weekly nimotuzumab schedules;
* To compare the two dosing schedules of nimotuzumab with respect to objective response rates and safety;
* To evaluate the overall safety and toxicity profiles of these two dose regimens of nimotuzumab;
* To evaluate trough levels and accumulation of nimotuzumab in serum of patients receiving the drug on weekly or 2-weekly regimens.